This phenomenon was first
This phenomenon was first noticed by Heinrich Hertz, who used a coil with a spark gap, though an early "voltaic" version of this phenomenon had been noted by Becquerel in 1839. Philipp Lenard noted this phenomenon's apparent contradiction of a theory proposed by Maxwell. The resolution of that problem posed by this effect saw the proposition of photons as quanta of light, which better explained the ejection of electrons noticed in this effect. For 10 points, name this physical effect that sees electrons emitted from matter that is struck by electromagnetic radiation, the explanation of which won Albert Einstein the 1921 Nobel Prize in physics.
This phenomenon was first noticed by Heinrich Hertz, who used a coil with a spark gap, though an early "voltaic" version of this phenomenon had been noted by Becquerel in 1839.
{photoelectric} effect